The attack on the US consulate in Benghazi, Libya, is the latest tragic reminder that America is at war.

Christopher Stevens, the US Ambassador to Libya, and the three other American dead are the latest victims of a war that started decades ago.

To those who knew him, Ambassador Stevens was a model of charm, decency and understanding. During Libya’s painful struggle to shake off despotism, he played a crucial role in helping mobilize international opinion in favor of the popular uprising. To many Libyans, he was not only a friend but something of a hero.

So who was responsible for the attack?

Initial reports suggested the Salafist group Ansar al-Sharia (Companions of the Sharia) might have been responsible, but the group quickly denied involvement.

The fact that the attack took place on the anniversary of 9/11 suggests that whoever staged it may have links with the terrorist group known as Al Qaeda in the Islamic Maghreb, given the Qaedists’ obsession with anniversaries.

The Benghazi raid coincided with a similar, but less tragic, attack on the US Embassy in Cairo. In both cases, the excuse was the publication on YouTube of the trailer for a movie in which Prophet Mohammad is supposedly insulted. The trailer reveals a mixture of ignorance and prejudice, but it has nothing to do with the US government or the American people.

All that the “ghazis” (raiders) in Cairo and Benghazi wanted was an excuse. They found it in the trailer.

The Cairo embassy and the Benghazi consulate are not the first US diplomatic missions to be stormed by self-styled “ghazis” of Islam. The seizure of the US embassy in Tehran in 1979 inspired other raids in Indonesia, Pakistan, Afghanistan, Iraq, Saudi Arabia, Yemen, Lebanon and Somalia — plus Kenya and Tanzania, where attacks on US embassies claimed thousands of lives.

America is at war not because Americans want it, but because there are Islamists who believe that the United States is the last remaining obstacle to their dream of subjugating the “Infidel” through terror dubbed as “jihad.”

Terrorists can always find excuses for attacks on US diplomats. Ayatollah Khomeini cited the late shah’s admission to a New York hospital. In 1980s Beirut, Hezbollah’s excuse was US intervention to prevent civil war in Lebanon.

In 1989, Salman Rushdie’s novel “Satanic Verses” was a pretext for attacks on US diplomatic missions in several Muslim nations — though Rushdie was a British citizen of Indian origin and the book’s publisher was also British.

America is at war not because it wants it, but because those who dream of reviving the Islamic caliphate fear its cultural and political attraction as much as its military and economic power.

In Libya, Islamist parties suffered a resounding defeat in the nation’s first free elections. Mahmoud Jibril, leader of the winning National Forces Alliance, has declared “close ties with the United Sates” as a key aspect of his program.

Mohammad Mursi, a member of the Muslim Brotherhood until his election as president of Egypt, has described the Arab Spring as “a movement for democracy and dignity,” not Islamic sharia. Tunisia’s principal Islamist leader, Rachid al-Ghannouchi, has visited the United States to demonstrate “admiration and respect” for America.

The Cairo and Benghazi raids reflect not just Islamo-fascist groups’ abiding hatred (mixed with resentful awe) for America, but also their growing fear that part of the Islamist movement may be succumbing to seduction by the United States.

The intensification of sectarian schism within Islam may encourage anti-American attacks as a diversionary tactic. Unable to agree on what Islam is, rival Islamist groups may focus on what Islam is not — and the United States, with its emphasis on individual freedoms and freedom of faith and speech, is a potent symbol of what they despise.